Calculate Pressure & Speed of Submerged Water Jet 100mm Away

  • Context: Undergrad 
  • Thread starter Thread starter JoachimSa
  • Start date Start date
  • Tags Tags
    Jet Submerged Water
Click For Summary
SUMMARY

The discussion focuses on calculating the pressure and speed of a submerged water jet impacting an object 100 millimeters from a nozzle. The setup involves a circular nozzle with a diameter of 2 millimeters, operating at a pressure of 400 bar and a flow rate of 60 liters per minute, located 100 meters below sea level in salt water. The velocity of the water jet varies with distance from the nozzle and radial distance from the flow centerline, complicating the calculations. A half angle of 11.8 degrees for the cone shape of the jet is suggested for practical calculations, but the interaction with the object depends on its geometry and the buoyancy effects of the salt water.

PREREQUISITES
  • Understanding of fluid dynamics principles
  • Familiarity with turbulent jet behavior
  • Knowledge of pressure and flow rate calculations
  • Experience with buoyancy effects in different fluid mediums
NEXT STEPS
  • Research the Bernoulli equation for fluid flow calculations
  • Study the principles of turbulent jet dynamics
  • Explore computational fluid dynamics (CFD) simulations for jet behavior
  • Investigate the effects of buoyancy in saltwater environments
USEFUL FOR

Engineers, fluid dynamics researchers, and professionals involved in high-pressure water jet applications, particularly those working in underwater environments or with turbulent flow scenarios.

JoachimSa
Messages
1
Reaction score
0
I am trying to calculate at what pressure and speed water from a high pressure water jet will hit an object 100 millimeters away from the nozzle opening, but i can't figure it out.

The nozzle will be used at approximately 100 meter below sea level in salt water. Its a circular nozzle with a diameter = 2 millimeters. The water from the water jet is at 400 bar and with a flow of about 60 liters per minute.

Does anyone know what formula to use?
 
I don't think there is a simple formula where you could just plug in numbers. There are certainly publications about that setup, you could check what they did to simulate the system.
 
A turbulent jet of liquid discharged into a large volume of the same liquid spreads out in a cone shape . Tests and simulations have determined that assuming a half angle of 11.8 deg for the cone is adequate for most practical calculations . Problem is that the velocity of flow varies not only with distance from nozzle but also with radial distance from the flow centreline . Velocity is highest on the flow centreline and fades away to zero at larger radial distances .

What actually happens when jet impinges on an object depends on the geometry of the object .
 
  • Like
Likes   Reactions: mfb and russ_watters
This becomes doubly difficult if your water jet is fresh water discharging into salt water, as it is now a turbulent buoyant jet. Generally speaking there is no simple solution to this problem (buoyant or not).
 

Similar threads

  • · Replies 32 ·
2
Replies
32
Views
10K
  • · Replies 17 ·
Replies
17
Views
2K
Replies
28
Views
2K
Replies
7
Views
1K
  • · Replies 3 ·
Replies
3
Views
18K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
6K
  • · Replies 13 ·
Replies
13
Views
21K
  • · Replies 2 ·
Replies
2
Views
2K